JP6544634B2 - Color filter and display device - Google Patents

Description

  The present invention relates to a color filter used in a display device and the display device.

  In recent years, development of various flat type display devices such as electronic paper and liquid crystal display devices has been advanced. As such a display device, there is known a reflection type display device which displays characters, images and the like by controlling reflected light of ambient light (hereinafter also referred to as "environmental light"). The application of the reflective display device has been advanced because it has excellent characteristics such as low power consumption, no eye fatigue, and good visibility in direct sunlight.

  In the above-described reflection type display device, when color image display is performed, a color filter having colored layers of a plurality of colors and a reflection type display element capable of performing white display and black display are usually used in combination. Be In such a reflective display device, environmental light is reflected by performing white display using a reflective display element, and desired color image display is performed by transmitting the reflected light to a color filter.

  FIG. 17 (a) is a plan view of a conventional color filter 10Y, and FIG. 17 (b) is an enlarged plan view of a region AY of FIG. 17 (a). As shown in FIG. 17B, in the color filter 10Y, a black black matrix layer 12Y having a predetermined pattern is provided in portions other than the colored layers 20Y, 30Y, and 40Y.

  In such a reflective display device, a display characteristic capable of expressing a texture close to paper when white display is desired is desired.

Japanese Patent Application Publication No. 2003-280044

  However, in the above-described conventional reflection type display device, even when white display is performed, the area displayed white is visually recognized as gray whose luminance is entirely reduced due to the influence of black matrix layer 12Y of black. Ru. Therefore, it is difficult to express the texture close to paper.

  The present invention has been made in consideration of these points, and it is an object of the present invention to provide a color filter and a display device capable of improving display characteristics.

A color filter according to an embodiment of the present invention is
A transparent substrate,
A white matrix layer for pixel division provided on the transparent substrate and forming a plurality of openings;
A transmission preventing layer provided on the inner surface of the plurality of openings of the white matrix layer;
A plurality of colored layers provided in the plurality of openings of the white matrix layer;
Equipped with

A color filter according to another embodiment of the present invention is
A transparent substrate,
A plurality of colored layers provided on the transparent substrate and arranged with a predetermined gap therebetween;
A white matrix layer for pixel division which is provided in the gap between the colored layers, an end portion of which runs on the end portion of the colored layer to form an opening for exposing the plurality of colored layers;
A light transmission preventing layer provided on an inner surface of the opening at an end of the white matrix layer which is mounted on the colored layer;
Equipped with

In the above color filter,
The transmission prevention layer may have a black matrix layer.

In the above color filter,
The transmission prevention layer may have a reflective layer that reflects light.

In the above color filter,
The reflective layer may be made of a metal layer.

In the above color filter,
The thickness of the white matrix layer may be thicker than the thickness of the colored layer.

In the above color filter,
A backing layer may be provided on the side of the white matrix layer opposite to the transparent substrate.

In the above color filter,
The backing layer may have a higher light shielding property than the white matrix layer.

In the above color filter,
The backing layer may have a black matrix layer.

In the above color filter,
The backing layer may have a second colored layer.

In the above color filter,
The backing layer may have a laminated second colored layer of multiple colors.

In the above color filter,
The white matrix layer may include a white pigment and a color pigment of a color different from that of the white pigment.

In the above color filter,
The white matrix layer and the plurality of first colored layers are disposed in a display area,
You may provide the frame part which encloses the said display area and has a white layer.

In the above color filter,
The white matrix layer and the plurality of first colored layers are disposed in a display area,
The display area may be surrounded by a frame portion having the black matrix layer.

A display device according to an embodiment of the present invention is
With the above color filter
A display element disposed to face the color filter;
Equipped with

In the above display device,
The display element may be a reflective display element for displaying white and black.

  According to the present invention, display characteristics can be improved.

It is a top view which shows schematic structure of the electronic paper which concerns on 1st Embodiment. It is a longitudinal cross-sectional view along the AA of FIG. It is the top view which looked at the color filter from the arrow I direction of FIG. It is a longitudinal cross-sectional view which shows the color filter of a comparative example. It is a top view which shows the other example of the color filter which concerns on 1st Embodiment. It is a longitudinal cross-sectional view of the color filter which concerns on 2nd Embodiment. It is a longitudinal cross-sectional view of the color filter concerning 3rd Embodiment. It is a top view which shows schematic structure of the electronic paper which concerns on 4th Embodiment. It is a longitudinal cross-sectional view along the BB line of the color filter of FIG. It is a longitudinal cross-sectional view of the color filter concerning 5th Embodiment. It is a longitudinal cross-sectional view of the color filter concerning 6th Embodiment. It is a longitudinal cross-sectional view of the electronic paper which concerns on 7th Embodiment. It is the top view which looked at the color filter from the arrow I direction of FIG. (A)-(d) is a figure which shows the manufacturing method of the color filter in 7th Embodiment. FIG. 15 is a view illustrating the method of manufacturing the color filter continued from FIG. 14; It is a figure which shows the relationship of chromaticity b * of a white matrix layer, and a calcination time for every calcination temperature. (A) is a top view of the conventional color filter, (b) is the top view which expanded field AY of (a).

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings attached to the present specification, for the sake of illustration and ease of understanding, the scale, vertical and horizontal dimensional ratios, etc. are appropriately changed from those of a real thing and exaggerated.

First Embodiment
First, with reference to FIG. 1, the entire electronic paper (reflection type display device) 100 will be described. In addition, although the electronic paper 100 is demonstrated as an example, the color filter 10 of this embodiment can also be applied to various display apparatuses of a reflection type or a transmission type, for example, a liquid crystal display apparatus and an organic EL display apparatus.

Electronic Paper FIG. 1 is a plan view showing a schematic configuration of the electronic paper 100 according to the first embodiment. FIG. 2 is a longitudinal sectional view taken along the line A-A of FIG.

  As shown in FIGS. 1 and 2, the electronic paper 100 includes a color filter 10 for electronic paper, and a reflective display element 80 arranged to face the color filter 10 to perform white display and black display. Is equipped. The color filter 10 is disposed closer to the viewer than the reflective display element 80.

  In FIG. 1, the electronic paper 100 is viewed from the observer side (color filter 10 side). As shown in FIG. 1, the color filter 10 has a display area A1 and a frame area A2 surrounding the outside of the display area A1. The frame area A2 has a function of hiding metal wiring and the like of the reflective display element 80 and the like, visible information such as product information is provided as necessary, and also has a function as a decorative part for improving the appearance design.

  As shown in FIG. 2, the color filter 10 is provided on a transparent substrate 11 and a transparent matrix 11, and a white matrix layer (hereinafter referred to as a WM layer) 12 for pixel section which forms a plurality of openings OP1. A plurality of colored layers (first colored layers) 20, 30, provided in the permeation prevention layer 50 provided on the inner surface 12c of the plurality of openings OP1 of the WM layer 12, and in the plurality of openings OP1 of the WM layer 12; 40, the frame portion 13 provided in the frame area A2, and the overcoat layer 14 provided on the WM layer 12 and the colored layers 20, 30, 40. The overcoat layer 14 may not be provided. Each of the colored layers 20, 30, 40 corresponds to one pixel.

  The WM layer 12, the light transmission preventing layer 50, and the plurality of colored layers 20, 30, 40 are disposed in the display area A1. The frame portion 13 surrounds the display area A1 and has a white layer 15. In the present embodiment, the frame portion 13 is configured of the white layer 15.

  The color filter 10 is disposed such that the overcoat layer 14 and the reflective display element 80 face each other. Therefore, the observer observes the electronic paper 100 from the transparent substrate 11 side (z direction side).

  Ambient light L1 is incident on the reflective display element 80 from the observer side via the color filter 10. The reflective display element 80 is configured to be able to control whether or not the environmental light L1 is reflected for each pixel, and performs white display by reflecting the environmental light L1, and black display by not reflecting the environmental light L1. I do. Therefore, the reflective display element 80 can display characters and images without using a backlight. Note that a front light may be provided to irradiate light to the reflective display element 80 from the observer side when the ambient light L1 is weak.

  The display method of the reflective display element 80 is not particularly limited, and any known one can be applied. For example, an electrophoretic method, a twist ball method, a powder transfer method (electronic powder fluid method, charged toner type method) Liquid crystal display system, thermal system (coloring system, light scattering system), electrochromic system, electrowetting system, magnetophoresis system and the like.

  Here, as an example, an electro-wetting-type reflective display element 80 will be schematically described. The reflective display element 80 includes a white substrate 81, a plurality of first transparent electrodes 82 and a plurality of metal wires 82a provided on the white substrate 81, and a hydrophobic material provided on the first transparent electrodes 82 and the metal wires 82a. Organic layer 83, a plurality of pixel sidewalls 84 provided on the hydrophobic insulating layer 83, an oil layer 85 provided between adjacent pixel sidewalls 84, an oil layer 85, and the pixel sidewall 84 It has a transparent liquid 86 and a second transparent electrode 87 provided on the liquid 86. A transparent substrate may be provided on the second transparent electrode 87. The non-transparent metal wiring 82 a is connected to, for example, the corresponding first transparent electrode 82.

  Each oil layer 85 is located on the corresponding first transparent electrode 82. One set of the first transparent electrode 82 and the oil layer 85 correspond to one pixel.

  When a voltage is not applied between the first transparent electrode 82 and the second transparent electrode 87, the oil layer 85 covers the hydrophobic insulating layer 83 between the adjacent pixel side walls 84, as illustrated. Since the oil layer 85 is colored, for example, in black, the incident environmental light L1 is not reflected by the oil layer 85, and a black display is performed.

  On the other hand, when a voltage is applied between the first transparent electrode 82 corresponding to a certain pixel and the second transparent electrode 87, although not shown, the oil layer 85 corresponding to this pixel has one pixel side wall. Then, the liquid 86 comes into contact with the hydrophobic insulating layer 83 at a position corresponding to the pixel. Thereby, in this pixel, the incident ambient light L1 reaches the white substrate 81, is reflected by the white substrate 81, and white display is performed.

  As described above, the electronic paper 100 reflects the ambient light L1 by performing white display using the reflective display element 80, and transmits the reflected light L2 to the color filter 10 to perform a desired color image display. Can.

Color Filter Referring now also to FIG. 3, color filter 10 will be described in detail. FIG. 3 is a plan view of the color filter 10 as viewed in the direction of arrow I in FIG. In addition, the overcoat layer 14 is abbreviate | omitted in FIG. 3 on account of description.

(Transparent substrate)
As the transparent substrate 11, various materials capable of appropriately supporting the WM layer 12, the permeation preventing layer 50, the colored layers 20, 30, 40, and the overcoat layer 14 and having transparency are used, for example, Glass, a polymer, etc. are used.

(WM layer and white layer)
The plurality of regions defined by the WM layer 12 are any of a region for the colored layer 20, a region for the colored layer 30, and a region for the colored layer 40, respectively. In the present embodiment, the WM layer 12 has a matrix-like pattern. The specific pattern of each area defined by the WM layer 12 is not particularly limited.

  Since the OD value (optical density) of the WM layer 12 and the white layer 15 is relatively low, if the thickness t1 is secured to increase the OD value, the metal wiring 82a on the reflective display element 80 side is the WM layer It may be viewed by the observer through the white layer 12 and the white layer 15. Therefore, it is preferable to set the thickness t1 of the WM layer 12 and the white layer 15 so as to suppress the visual recognition of the metal wiring 82a and the like. The thickness t1 of the WM layer 12 and the white layer 15 may be, for example, 5 to 20 μm, and in the illustrated example, is thicker than the thickness t2 of the plurality of colored layers 20, 30, 40. The thickness t1 may be thinner than the thickness t2 as long as the visual recognition of the metal wires 82a and the like can be suppressed.

  The white layer 15 surrounds the WM layer 12 and is integrally formed with the WM layer 12. The WM layer 12 and the white layer 15 are formed of the same material.

  The WM layer 12 and the white layer 15 contain at least a white pigment in a resin binder made of a cured product of a photosensitive resin, and exhibit white.

[White pigment]
As the white pigment, for example, titanium oxide, silica, talc, kaolin, clay, barium sulfate, calcium hydroxide and the like can be used.

  Although the content of the white pigment depends on the color expressed by the WM layer 12 and the white layer 15, the content of the white pigment and the resin binder is shown as a percentage of the amount of the white pigment to the total solid content of the WM layer 12 and the white layer 15. The pigment concentration is, for example, 10 to 80%.

[Resin binder: photosensitive resin etc.]
The resin of the resin binder is basically not particularly limited, but in view of durability and the like, it is preferable to use a curable resin. When using curable resin as resin of a resin binder, the WM layer 12 and the white layer 15 are formed as a layer which consists of hardened | cured material of curable resin.

  As the curable resin, a photosensitive resin that can be cured by active energy rays such as ultraviolet rays, electron beams, and visible rays can be used. By using a photosensitive resin, the WM layer 12 and the white layer 15 can be formed by a photolithography method capable of forming a fine pattern.

  Examples of the photosensitive resin include photosensitive resins having a photoreactive group such as reactive vinyl group such as acrylic resin, epoxy resin, polyimide resin, polyvinyl cinnamate resin, cyclized rubber, etc. More than species can be used. In the case of an acrylic resin, for example, a photosensitive resin composed of an alkali soluble resin, a polyfunctional acrylate monomer, a photopolymerization initiator, other additives and the like can be used as a resin component of the resin binder.

  As the alkali-soluble resin, one or more kinds of methacrylic acid ester copolymer such as benzyl methacrylate-methacrylic acid copolymer, and a cardo resin such as epoxy acrylate having a bisphenol fluorene structure can be used.

Examples of multifunctional acrylate monomers include one or more of trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, etc. It can be used.
In the present invention, (meth) acrylate means either methacrylate or acrylate.

  As the photopolymerization initiator, one or more kinds of alkylphenone type, oxime ester type, triazine type, titanate type and the like can be used. For example, in the case of alkylphenone, (2-methyl-1 [4- (methylthio) phenyl] -2-morpholinopropan-1-one (IRGACURE (registered trademark) 907, manufactured by BASF Japan Ltd.)), 2- Benzyl-2-dimethylamino-1- (4-monophoriophenyl) butanone-1 (IRGACURE (registered trademark) 369, manufactured by BASF Japan Ltd.), and in the case of an oxime ester, 1,2-octanedione, 1- [1 4- (phenylthio) phenyl]-, 2- (O-benzoyloxime) (IRGACURE (registered trademark) OXE01, manufactured by BASF Japan Ltd.) and the like can be used.

  The resin binder may further contain various known additives such as a solvent, a photosensitizer, a dispersant, a surfactant, a stabilizer, and a leveling agent.

[Formation of WM layer and white layer]
The WM layer 12 and the white layer 15 can be formed by, for example, a photolithography method using a white-based photosensitive resin composition containing at least a white pigment and an uncured material of a photosensitive resin.

  The method of applying the white photosensitive resin composition on the surface of the transparent substrate 11 may be, for example, a known coating method such as spin coating, roll coating, die coating, spray coating or bead coating. it can.

  After applying the white-based photosensitive resin composition, patterning is performed through predetermined steps such as exposure, development, baking (heat treatment) and the like using a photolithographic technique, whereby a part of the surface of the transparent substrate 11 is formed. Then, the WM layer 12 and the white layer 15 of a predetermined pattern can be formed.

(Transmission prevention layer)
The transmission preventing layer 50 is not provided on the surface 12 b of the WM layer 12 on the side of the reflective display element 80. The portion on the transparent substrate 11 side of the permeation prevention layer 50 is sandwiched between the colored layers 20, 30 and 40 and the WM layer 12. The portion on the reflective display element 80 side of the transmission preventing layer 50 does not face the colored layers 20, 30, 40.

  The transmission preventing layer 50 is a layer that prevents or suppresses transmission of reflected light that is visible light. The light transmission preventing layer 50 includes, for example, a black matrix layer (hereinafter referred to as a BM layer) 51 having a light shielding property. In the present embodiment, the permeation prevention layer 50 is composed of the BM layer 51. The thickness of the BM layer 51 is not particularly limited as long as a desired light shielding property can be obtained, but may be, for example, 1 to 5 μm.

  The material of the BM layer 51 is not particularly limited as long as it has a desired light shielding property, and examples thereof include a resin composition containing a black colorant such as carbon black and titanium black. As resin used for this resin composition, photosensitive resin which has reactive vinyl groups, such as an acrylate type, a methacrylate type, polyvinyl cinnamate type, or a cyclization rubber type, is used, for example.

  The BM layer 51 can be formed by photolithography after the WM layer 12 is formed.

(Colored layer)
As shown in FIGS. 2 and 3, the colored layers 20, 30 and 40 are arranged in a matrix. The colored layers 20, 30, 40 are provided in the area defined by the WM layer 12, that is, in the opening OP1. The thickness of the colored layers 20, 30, 40 is approximately equal.

  The colored layer 20, the colored layer 30, and the colored layer 40 are repeatedly arranged in this order in the x direction. A plurality of sets of colored layers 20, 30, and 40 repeatedly arranged in this manner are arranged in the y direction. The arrangement order of the colored layers 20, 30, 40 and the shape as viewed from the side of the reflective display element 80 are not limited to the illustrated example.

  For example, the colored layer 20 is a red colored layer that transmits red light, the colored layer 30 is a green colored layer that transmits green light, and the colored layer 40 is a blue colored layer that transmits blue light. Thus, each colored layer 20, 30, 40 is configured to transmit light of the corresponding color. Other colored layers, such as a white colored layer that transmits white light, may be further provided.

  After forming the WM layer 12 and the BM layer 51, each of the colored layers 20, 30, 40 is formed by patterning the photosensitive layer material having photosensitivity by a photolithography method including an exposure step and a development step. Layer. As a coloring layer material to be patterned by the photolithography method, any of negative type and positive type coloring layer materials may be used. In addition, the colored layers 20, 30, 40 may be formed in any order.

[Material for colored layer]
Next, a first colored layer material (hereinafter, first material) constituting each colored layer 20, 30, 40, a second colored layer material (hereinafter, second material), and a third colored layer material Hereinafter, the third material will be described. Each of the first to third materials contains a pigment dispersion containing a pigment or dye of each color and a dispersing agent, a photoinitiator, a clearing agent containing a polymer or a monomer, a surfactant and the like. Among these, a photoinitiator is what generate | occur | produces a radical component by being irradiated with light. Further, the clear agent contains at least a component which is cured by causing a polymerization reaction by radicals generated by the photoinitiator and which becomes a component which becomes capable of dissolving the unexposed area by the subsequent development.

(Comparative example)
Here, the color filter 10X of the comparative example will be described. As shown in FIG. 4, in the color filter 10 </ b> X of the comparative example, the light transmission preventing layer is not provided on the inner surface 12 c of the opening OP <b> 1 of the WM layer 12.

  As described above, the ambient light L1 incident from the viewer side and transmitted through the colored layer (for example, the colored layer 30) of a certain pixel is reflected by the reflective display element 80. At this time, there may also be reflected light L3 directed to the inner surface 12c of the opening OP1 of the WM layer 12 in accordance with the incident angle or the like of the environmental light L1. Such reflected light L3 passes through the WM layer 12 having a relatively low OD value, enters the colored layer (for example, the colored layer 40) of the next pixel, and passes through the colored layer 40 to the viewer side. To reach. Thereby, the reflected light L3 visually recognized by the observer side has the color which the color of the colored layer 30 and the color of the colored layer 40 mixed, for example. As described above, in the comparative example, color mixture may occur between two adjacent pixels, and thus the display quality may be degraded.

  On the other hand, according to the present embodiment, since the transmission preventing layer 50 is provided on the inner surface 12c of the plurality of openings OP1 of the WM layer 12, the opening OP1 of the WM layer 12 is reflected by the reflective display element 80. Transmission of the reflected light L3 directed to the inner surface 12c of the light shielding layer 50 is prevented. Therefore, since this reflected light L3 does not enter into the coloring layer of the next pixel, color mixing can be prevented. Therefore, the deterioration of the display quality can be suppressed.

  The transmission preventing layer 50 may be provided on a part of the inner surface 12 c of the opening OP 1 of the WM layer 12 as long as the desired color mixing preventing function can be exhibited.

  Furthermore, according to the present embodiment, since the white WM layer 12 for pixel division is provided, the white-displayed area in the display area A1 is visually recognized as white as a whole. That is, when white is displayed, the observer visually recognizes the reflected light from the reflective display element 80 transmitted through the predetermined colored layers 20, 30, 40 as white, and the environmental light is reflected by the WM layer 12 White light will also be visible. By also visually recognizing the white light reflected by the WM layer 12, it is possible to increase the brightness of the area displayed white. Therefore, the texture close to paper can be expressed. That is, the display characteristics can be improved.

  In addition, the white frame portion 13 can provide the electronic paper 100 with high designability. In particular, when the entire display area A1 is displayed in white, since the frame portion 13 and the display area A1 are integrally viewed in white, it is possible to exhibit a design which is not provided in the prior art. Moreover, since it is not necessary to separately provide a front surface protection plate on which the frame portion 13 is formed, the electronic paper 100 can be reduced in weight.

The color filter 10 may not include the frame portion 13.
In addition, the color filter 10 may include a colored layer of one color, and may be configured as a single color filter.
Further, the permeation prevention layer 50 may be configured by at least one colored layer instead of the BM layer 51.

  Further, as shown in FIG. 5, each of the colored layers 20, 30, 40 may be rectangular when viewed from the viewer side or the reflective display element 80 side, and may be provided in a stripe shape.

Second Embodiment
The second embodiment is different from the first embodiment in that the anti-transmission layer 50 has a reflection layer 52.

  FIG. 6 is a longitudinal sectional view of a color filter 10A according to the second embodiment. FIG. 6 corresponds to FIG. The anti-transmission layer 50 of the color filter 10A has a reflection layer 52 for reflecting light, thereby preventing transmission of the reflected light. In the present embodiment, the transmission preventing layer 50 is composed of the reflective layer 52, and the reflective layer 52 is composed of a metal layer. The thickness of the reflective layer 52 is not particularly limited as long as a desired light shielding property can be obtained, but may be, for example, 100 nm to 5 μm.

  The material of the reflective layer 52 is not particularly limited as long as it has desired reflective characteristics, and examples thereof include aluminum and silver.

  The reflective layer 52 is formed after forming the WM layer 12 and before forming the colored layers 20, 30, 40. As a method of forming the reflective layer 52, first, a metal thin film is formed on the WM layer 12 and the transparent base 11 in the opening OP1 using a known metal thin film forming method. As a metal thin film formation method, a vacuum evaporation method, sputtering method, CVD method etc. can be mentioned, for example. Thereafter, an etching process is performed using a photolithography method, and the metal thin film located other than the inner surface 12c of the opening OP1 of the WM layer 12 can be removed to form the reflective layer 52.

  According to the present embodiment, the reflected light L3 is reflected by the reflective layer 52, passes through the colored layer of the original pixel, and is emitted to the observer side. Therefore, color mixing can be prevented, and the reflected light L3 can also be used for image display to improve the luminance compared to the first embodiment. That is, ambient light can be used more efficiently for image display.

Third Embodiment
In the first embodiment, a part of the ambient light passes through the WM layer 12 and the white layer 15, so depending on the thickness t1 of the WM layer 12 and the white layer 15, the content of the white pigment, etc. The metal wiring 82 a and the like on the display element 80 side may be viewed by the observer through the WM layer 12 or the white layer 15. As the thickness t1 of the WM layer 12 and the white layer 15 is increased, the metal wiring 82a and the like can be made more difficult to visually recognize, but in the thick WM layer 12, fine patterning by photolithography is difficult.

  Therefore, in the third embodiment, the backing layer 16 is provided. Hereinafter, differences from the first embodiment will be mainly described.

  FIG. 7 is a longitudinal sectional view of a color filter 10B according to the third embodiment. FIG. 7 corresponds to FIG. As shown in FIG. 7, the color filter 10 </ b> B further includes a backing layer 16 in addition to the configuration of the color filter 10 of the first embodiment.

  The backing layer 16 is provided on the surface of the WM layer 12 and the white layer 15 opposite to the transparent substrate 11 and has a higher light shielding property than the WM layer 12. That is, the backing layer 16 has a higher OD value than the WM layer 12. The backing layer 16 has a black matrix layer 17. In the present embodiment, the backing layer 16 is composed of the BM layer 17. The BM layer 17 has the same matrix-like pattern as the WM layer 12.

  In addition, the BM layer 17 is integrally formed with the BM layer 51 of the permeation prevention layer 50. That is, the material of the BM layer 17 is the same as the material of the BM layer 51.

  After the WM layer 12 and the white layer 15 are formed, the BM layer 17 can be formed simultaneously with the BM layer 51 by, for example, a photolithography method. Therefore, the number of manufacturing steps does not increase as compared with the first embodiment.

  The BM layer 17 as such a backing layer 16 shields part of the ambient light that passes through the WM layer 12 and the white layer 15 and travels to the reflective display element 80.

  Therefore, according to the present embodiment, while maintaining the thickness of the WM layer 12 to such an extent that a desired fine pattern can be formed by the photolithography method, the reflective display element 80 side via the WM layer 12 or the white layer 15 Can be prevented from being visually recognized.

  In addition, since most of the ambient light is reflected by the WM layer 12, relatively high luminance is obtained when white is displayed even if the backing layer 16 is present, and the WM layer 12 is visually recognized as a white-based color Be done. Therefore, as in the first embodiment, the texture close to paper can be expressed. However, as the thickness of the WM layer 12 is thinner, the WM layer 12 is perceived as a color close to gray due to the influence of the black color of the BM layer 17 of the backing layer 16. It is necessary to increase the thickness of the layer 12.

  The thickness of the white layer 15 of the frame portion 13 may be increased without providing the backing layer 16. The white layer 15 may have a lower processing accuracy than the WM layer 12 and can be easily processed even if it is thick.

Fourth Embodiment
The fourth embodiment differs from the third embodiment in that the frame portion 13 is formed of a BM layer. Hereinafter, differences from the third embodiment will be mainly described.

  FIG. 8 is a plan view showing a schematic configuration of the electronic paper 100C according to the fourth embodiment. FIG. 8 corresponds to FIG. FIG. 9 is a longitudinal cross-sectional view of the color filter 10C of FIG. 8 taken along the line B-B.

  As shown in FIGS. 8 and 9, the frame portion 13 surrounding the display area A1 is formed of a BM layer 18 instead of the white layer 15. The BM layer 51 of the permeation prevention layer 50, the BM layer 17 of the backing layer 16, and the BM layer 18 of the frame portion 13 are formed of the same material. Although the thickness of the BM layer 18 of the frame portion 13 is thicker than the thickness of the BM layer 17 of the backing layer 16 in the illustrated example, the thickness may be substantially the same.

  According to the present embodiment, the frame portion 13 configured from the BM layer 18 is visually recognized as black. Therefore, the electronic paper 100B can have designability different from that of the second embodiment.

  Further, since the light blocking property of the BM layer 18 is high, the metal wiring 82a and the like on the reflective display element 80 side can be prevented from being visually recognized through the frame portion 13 as in the second embodiment.

  Further, since the BM layer 51 of the light transmission preventing layer 50, the BM layer 17 of the backing layer 16, and the BM layer 18 of the frame portion 13 can be formed in the same step, the number of manufacturing steps is increased compared to the third embodiment. There is nothing to do.

  In the first embodiment, the frame portion 13 may be formed of the BM layer 18.

Fifth Embodiment
The fifth embodiment differs from the third embodiment in that the backing layer 16 is composed of a colored layer. Hereinafter, differences from the third embodiment will be mainly described.

  FIG. 10 is a longitudinal sectional view of a color filter 10D according to the fifth embodiment. FIG. 10 corresponds to FIG. As shown in FIG. 10, the backing layer 16 has laminated colored layers (second colored layers) 20D, 30D, and 40D of a plurality of colors. The colored layer 20D is formed in the same step using the same material as the colored layer 20. The colored layer 30D is formed in the same step using the same material as the colored layer 30. The colored layer 40D is formed in the same step using the same material as the colored layer 40.

  The thickness of the colored layers 20D, 30D, and 40D may be set to such an extent that the required light shielding property can be exhibited. The backing layer 16 may be composed of a smaller number of layers than the number of colored layers 20, 30 and 40 in the display area A1, for example, one colored layer.

  Since such a backing layer 16 has a higher light shielding property than the WM layer 12, as in the third embodiment, the metal wiring 82a etc. on the reflective display element 80 side can be viewed through the WM layer 12 or the white layer 15. It can be difficult to do. Thus, the effects of the third embodiment can be obtained.

(Modification of the fifth embodiment)
Various modifications can be made to the fifth embodiment. Hereinafter, an example of a modification is demonstrated.

[Combination of backing layer and color adjustment layer]
By adjusting the number, thickness, and color of the colored layers 20D, 30D, and 40D of the backing layer 16, it is also possible to adjust the color visually recognized through the WM layer 12. That is, the backing layer 16 may have a color adjustment function as a color adjustment layer in addition to the light shielding function. This makes it possible to express the texture of paper colored in light brown or light water color.

  The backing layer 16 as a layer which also serves as a color adjustment layer may contain, for example, a black pigment and a chromatic color pigment in a resin binder, and may exhibit a blackish color having a blackish color but having a hue. . However, as a matter of course, the black layer is not the backing layer 16 as a layer also serving as a color adjustment layer, but the backing layer 16. The reason is that without light reflection from the black layer, it is not possible to adjust the lightness or hue of the WM layer 12 by the light intensity or spectral distribution of the light reflection. Thus, simple black is excluded from the color of the color adjustment layer, but gray of the same achromatic color is a category of the color adjustment layer.

[Color adjustment layer]
When the light shielding function is not necessary, the backing layer 16 may have a lower light shielding property than the WM layer 12. In this case, the backing layer 16 functions as a color adjustment layer that adjusts the color viewed through the WM layer 12. The color adjustment layer is a layer exhibiting a color different from the color exhibited by the WM layer 12, and is a layer formed at a position overlapping the WM layer 12.

  With such a color adjustment layer, the color viewed through the WM layer 12 can be a color in which at least the color of the WM layer 12 and the color of the color adjustment layer are combined. For this purpose, the WM layer 12 positioned on the viewer side of the color adjustment layer is formed as a layer having transparency that is greater than the degree at which the color of the color adjustment layer is reflected.

  Although the number of manufacturing steps is increased, the backing layer 16 may have a colored layer dedicated to the backing layer 16. Such a colored layer has a color different from that of the colored layers 20, 30, and 40 in the display area A1. For example, a blue coloring layer thinner than the blue color of the coloring layer 40 can be provided as the backing layer 16 to express the texture of light light blue colored paper. This improves the freedom of color setting. In addition, a colored layer having an OD value higher than that of each of the colored layers 20, 30, and 40 may be provided.

  As in the fourth embodiment, the frame portion 13 may be formed of the BM layer 18.

Sixth Embodiment
The sixth embodiment differs from the first embodiment in that the WM layer 12 is colored in a color other than white.

  FIG. 11 is a longitudinal sectional view of a color filter 10E according to a sixth embodiment. FIG. 11 corresponds to FIG. The WM layer 12E and the white layer 15E include a white pigment and a color pigment of a color different from that of the white pigment. Thereby, the WM layer 12E and the white layer 15E can express white-based colors such as ivory other than white and light gray.

  As the color pigment, for example, a red pigment, a yellow pigment, a blue pigment, a green pigment, a violet pigment, a black pigment and the like can be used.

  For the red pigment, for example, red pigments such as diketopyrrolopyrrole type, anthraquinone type and perylene type can be used, and as yellow pigments, for example, yellow pigments such as isoindoline type and anthraquinone type can be used For blue pigments, for example, blue pigments such as copper phthalocyanine and anthraquinone can be used. For green pigments, for example, green pigments such as phthalocyanine and isoindoline can be used. For purple pigments In addition, purple pigments such as quinacridone and dioxazine can be used.

  More specifically, the color pigment may be, for example, anthraquinone pigment red 177 (PR177) as a red pigment, isoindoline pigment yellow 139 (PY139) as a yellow pigment, and copper phthalocyanine as a blue pigment. Pigment Blue PB 15: 6 (PB 15: 6), and the like can be used.

  As the purple pigment, quinacridone-based quinacridone (PV19), dioxazine-based dioxazine violet (PV23), and the like can be used.

  As the black pigment, for example, titanium black (lower order titanium oxide, titanium oxynitride, etc.), carbon black and the like can be used.

  A black pigment can be used in a color with reduced lightness by using it together with a white pigment or together with a white pigment and a color pigment of a color other than the white pigment.

  The particle size of the coloring pigment is usually 1 μm or less in average particle diameter, preferably about 0.03 to 0.5 μm.

  The color pigment may be appropriately selected according to the color of the white color to be expressed. Therefore, the color pigments may be used alone or in combination of two or more color pigments of the same type or different colors.

  The WM layer 12E and the white layer 15E can adjust the opacity or transparency of the WM layer 12E and the white layer 15E themselves depending on the film thickness and the content of the color pigment. The thickness of the WM layer 12E is, for example, 5 to 20 μm, as in the first embodiment.

  Although the content of the color pigment depends on the transparency of the white color expressed by the WM layer 12E and the white layer 15E, the compactness expected for the color of the white color, etc., the WM layer 12E containing the color pigment and the resin binder The pigment concentration is, for example, usually about 1 to 60%, as a percentage of the amount of color pigment to the total solid content of the white layer 15E. In other words, the coloring pigment is usually in the range of about 11 to 60 parts by mass with respect to 100 parts by mass of the total solid content of the WM layer 12E and the white layer 15E.

According to this embodiment, when white is displayed, the color of the WM layer 12E can express the texture of the paper colored in light brown, light water, or the like.
Further, high designability can be provided by the white color of the white layer 15E.

  In the above third to sixth embodiments, the transmission preventing layer 50 may have the reflection layer 52 of the second embodiment.

Seventh Embodiment
The seventh embodiment is different from the first embodiment in that the WM layer 12F is formed after the colored layers 20, 30, and 40 are formed.

  FIG. 12 is a longitudinal sectional view of an electronic paper 100F according to a seventh embodiment. FIG. 12 corresponds to FIG. FIG. 13 is a plan view of the color filter 10F as viewed in the direction of arrow I in FIG. 12 (on the side of the reflective display element 80). Hereinafter, differences from the first embodiment will be mainly described.

  As shown in FIG. 13, the colored layers 20, 30, and 40 are arranged in a matrix. The colored layer 20, the colored layer 30, and the colored layer 40 are repeatedly arranged in this order with a gap s1 in the x direction. A plurality of sets of the coloring layers 20, 30, 40 repeatedly arranged in this manner are arranged with a predetermined gap s2 in the y direction.

  The WM layer 12F has a matrix-like pattern. The specific pattern of each area defined by the WM layer 12F is not particularly limited.

  The WM layer 12F is provided in the gaps s1 and s2 between the colored layers 20, 30, and 40, and the ends thereof run on the ends (edges) of the colored layers 20, 30, and 40, and a plurality of colored layers 20, 30 are obtained. , 40 are formed in the plurality of openings OP1. That is, the end portions of the colored layers 20, 30, 40 are sandwiched between the WM layer 12F and the transparent substrate 11. Further, in the WM layer 12F, the width (= s1) of the surface 12a on the transparent substrate 11 side is smaller than the width d1 of the surface 12b opposite to the transparent substrate 11. Therefore, as shown in FIG. 13, when viewed from the reflective display element 80 side, the end portions of the colored layers 20, 30, 40 are covered with the WM layer 12 F, and the colored layers 20, 30, 40 A part of the surface on the side of the reflective display element 80 is exposed from the opening OP1 of the WM layer 12F. Such a structure originates in the manufacturing method mentioned later.

  The permeation prevention layer 50F is formed of the BM layer 51F, and is provided on the inner surface 12c of the opening OP1 at the end that rides on the colored layers 20, 30, and 40 of the WM layer 12F. Therefore, the transmission preventing layer 50F is provided in a square loop shape corresponding to the shape of the opening OP1 as viewed from the reflective display element 80 side. Each colored layer 20, 30, 40 is exposed inside the square loop shaped anti-reflection layer 50F.

Method of Manufacturing Color Filter Next, a method of manufacturing the color filter 10F will be described with reference to FIG.

  First, the entire manufacturing method of the color filter 10F will be described with reference to FIGS. 14 (a) to 14 (d) and FIG. In the method of manufacturing the color filter 10F, the transparent substrate 11 is prepared, and the transparent substrate 11 is arranged along the x direction with a predetermined gap s1 open and along the y direction with a predetermined clearance s2 open. After forming the colored layers 20, 30, 40, forming the colored layers 20, 30, 40 (see FIGS. 14A to 14C) and forming the colored layers 20, 30, 40, the colored layer 20, A WM layer forming step (see FIG. 14 (d)) for forming the WM layer 12F in the gaps s1 and s2 between 30 and 40 (see FIG. 14D) and a transmission preventing layer forming step for forming the transmission preventing layer 50F after forming the WM layer 12F And (see FIG. 15). That is, in the colored layer forming step, the plurality of colored layers 20, 30, 40 are formed by leaving the WM layer forming region where the WM layer 12F is formed in the WM layer forming step. In FIGS. 14 (a) to 14 (d) and 15, the arrangement along the y direction is not shown.

  Among these, the colored layer forming step includes a first colored layer forming step, a second colored layer forming step, and a third colored layer forming step. In the first colored layer forming step, a plurality of colored layers 20 are formed on the transparent substrate 11 so as to be aligned along the x direction at a predetermined pitch and to be spaced along the y direction with a gap s2 (FIG. a) see).

  In the second colored layer forming step, after the first colored layer forming step, the transparent base 11 is arranged along the x direction at a predetermined pitch so as to provide a gap s1 with each colored layer 20, A plurality of colored layers 30 aligned along the y direction are formed with the gap s2 open (see FIG. 14B).

  In the third colored layer forming step, after the second colored layer forming step, the transparent substrate 11 is arranged along the x direction at a predetermined pitch so as to provide gaps s1 with the colored layers 20 and 30. At the same time, the plurality of colored layers 40 aligned along the y direction are formed with the gap s2 open (see FIG. 14C).

  In FIGS. 14 (a) to (d) and FIG. 15, the specific processing carried out in each step is shown on the right side, and on the left side, the transparent after the processing in each step is carried out. A cross-sectional view of each layer formed on the substrate 11 is shown.

(First colored layer forming step)
Hereinafter, each colored layer forming step and the WM layer forming step will be described. First, the first colored layer forming step will be described in detail.

[Coating step]
First, a coating solution for the first colored layer (hereinafter, first coating solution) obtained by mixing the first material and the solvent described in the first embodiment is applied onto the transparent substrate 11. The method of applying the first coating liquid on the transparent substrate 11 is not particularly limited, and spin coating method, ink jet method, casting method, dipping method, bar coating method, blade coating method, roll coating method, gravure coating A method, a flexographic printing method, a spray coating method, etc. can be used suitably.

[Pre-baking process]
Next, the first coating liquid applied on the transparent substrate 11 is heated, thereby removing the solvent in the first coating liquid. As a result, the first material is obtained on the transparent substrate 11. The heating conditions in such pre-baking treatment are not particularly limited, and the temperature and the heating time in the pre-baking treatment are appropriately set according to the type and the weight% of the solvent contained in the first coating liquid. Such pre-baking treatment is generally carried out by using a clean oven. In addition, before the pre-baking process, the drying process for partially removing the solvent in a 1st coating liquid, for example, reduced-pressure-drying process may be implemented.

[Exposure process]
Next, exposure light is irradiated to the first material through the exposure mask. In this case, the openings of the exposure mask are arranged along the x direction and the y direction so as to correspond to the pattern of the colored layer 20. As a result of the exposure process, the portion of the first material irradiated with the exposure light is cured. The light used as the exposure light is not particularly limited, and various lights may be appropriately used according to the photosensitive characteristics of the first material.

[Development process]
Thereafter, the exposed first material is developed, whereby the portion of the first material which has not been irradiated with the exposure light is dissolved in the developer.

[Firing process]
Finally, the developed first material remaining on the transparent substrate 11 is baked, for example, at 230 ° C. or higher. As a result, as shown in FIG. 14A, a plurality of colored layers 20 aligned along the x direction with a predetermined pitch and spaced along the y direction with the gap s2 open are formed on the transparent substrate 11. In addition, a calcination temperature is not specifically limited, According to a 1st coating liquid, it can set suitably.

(Second colored layer forming step)
In the second colored layer forming step, a coating liquid for a second colored layer (second coating liquid) obtained by mixing the above-described second material and a solvent is used as a coating liquid, and The only difference is that the openings of the exposure mask are arranged to correspond to the pattern of the colored layer 30, and the other points are substantially the same as the first colored layer forming step described above. Therefore, the detailed description about a 2nd colored layer formation process is omitted.

(Third colored layer forming step)
In the third colored layer forming step, a third colored layer coating solution (third coating solution) obtained by mixing the above-described third material and a solvent is used as a coating solution, and The only difference is that the openings of the exposure mask are arranged to correspond to the pattern of the colored layer 40, and the other points are substantially the same as the first colored layer forming step described above. Therefore, the detailed description on the third colored layer forming step is also omitted.

(WM layer formation process)
Next, the WM layer forming process will be described. The WM layer forming step is, for example, a WM coating liquid obtained by mixing a white photosensitive resin composition containing at least a white pigment and an uncured photosensitive resin as a coating liquid, and a solvent. Except that the openings of the exposure mask are arranged in a matrix so that the openings OP1 are formed on the colored layers 20, 30, and 40, and the other points are the same as those described above. Is substantially the same as the first colored layer forming step of Therefore, the detailed description on the WM layer forming process is also omitted.

(Permeation prevention layer formation process)
Next, the permeation prevention layer forming process will be described. In the permeation prevention layer forming step, a BM coating liquid obtained by mixing, for example, a photosensitive resin composition containing at least a black coloring material and an uncured photosensitive resin as a coating liquid, and a solvent And the opening 61 of the exposure mask 60 is formed such that the BM layer 51F is formed on the inner surface 12c of the opening OP1 at the end which rides on the colored layers 20, 30, and 40 of the WM layer 12F. Only the points are different, and the other points are substantially the same as the first colored layer forming step described above. Note that FIG. 15 also shows the exposure mask 60 for the purpose of explanation.
The color filter 10F is obtained by the above manufacturing method.

  The WM layer 12F may be formed without using the photolithography method. In this case, as the WM coating liquid, one containing a white pigment, a clear agent containing a polymer or a monomer, a surfactant, a solvent and the like may be used. Among these, the clearing agent contains at least a component that causes a polymerization reaction to be cured by heating. Then, for example, after the coloring layer forming process, the coloring layer is formed using an inkjet head having a nozzle capable of discharging a droplet having a diameter smaller than the width of the gaps s1 and s2 between the coloring layers 20, 30, and 40. The WM coating liquid may be applied to the gaps s1 and s2 between 20, 30 and 40 with high accuracy. By adjusting the amount of the WM coating liquid to be applied, the WM coating liquid overflows from between the colored layers 20, 30, 40, and the WM coating liquid is also coated on the end of the colored layers 20, 30, 40 be able to. After this, a drying process for removing the solvent in the WM coating liquid may be performed, and finally, the WM coating liquid may be subjected to a baking process. Thereby, the above-mentioned WM layer 12F is formed.

  Here, in the first embodiment, after the WM layer 12 is formed on the transparent substrate 11, a plurality of colored layers 20, 30, 40 are formed in the opening OP1 of the WM layer 12. Since the method of forming the colored layers 20, 30, 40 is the same as that of this embodiment, each time the colored layers 20, 30, 40 are formed, for example, the colored layers 20, 30, 40 are heated and fired at about 230.degree. At this time, since the WM layer 12 is also heated, the WM layer 12 may be heated at a high temperature for a long time to be discolored. For example, as shown in FIG. 16, the chromaticity b * of the WM layer 12 before heating (baking time 0 minutes) is about 0.8, but the baking temperature is 230 ° C., and the total baking time is 125 minutes , The chromaticity b * of the WM layer 12 increases to 7.5 or more. At such a chromaticity b *, the WM layer 12 is visually recognized in a cream color close to yellow.

  If the firing temperature is lowered below 230 ° C., the chromaticity b * can be lowered even at the same firing time of 125 minutes, and a color closer to white can be maintained. However, at temperatures lower than 230 ° C., organic substances may remain in the colored layer. Therefore, the remaining organic substance may be released as a gas, which reduces the reliability of the color filter. Therefore, in order to ensure reliability, it is preferable to bake at about 230 ° C. or higher.

  Further, in the first embodiment, in the process of forming the WM layer 12 using the photolithography method, the light for exposure that has entered the WM layer 12 is diffused because the WM layer 12 is white, and thus exposure is performed. Exposure is performed in a range wider than the width of the opening of the mask. Therefore, the width of the WM layer 12 is larger than the width of the opening of the exposure mask. Therefore, it is not easy to control the width of the WM layer 12 with high accuracy.

  On the other hand, according to the present embodiment, since the WM layer 12F is formed after forming the colored layers 20, 30, 40, the heat applied when forming the colored layers 20, 30, 40 is WM Not added to layer 12F. Therefore, the time during which the WM layer 12F is heated at high temperature can be made shorter than in the first embodiment. Therefore, it is possible to prevent yellowing of the color of the WM layer 12F without lowering the baking temperature of the colored layers 20, 30, 40, and to form the WM layer 12F having a color closer to white. Since it is not necessary to lower the firing temperature, it is possible to suppress the decrease in the reliability of the color filter 10F.

  For example, when the firing time is about 10 minutes, as shown in FIG. 16, the chromaticity b * is less than 2 even if the firing temperature is 230 ° C.

  Further, since the width of the surface 12a on the transparent base 11 side of the WM layer 12F is equal to the gap s1 between the colored layers 20, 30, and 40 formed earlier, the width of the surface 12a of the WM layer 12F is highly accurate And it can control easily.

In the seventh embodiment, the transmission preventing layer 50 may have the reflective layer 52 of the second embodiment.
The seventh embodiment may be combined with the third to sixth embodiments.

  While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the invention. These embodiments can be implemented in other various forms, and various omissions, replacements, and modifications can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the invention described in the claims and the equivalents thereof as well as included in the scope and the gist of the invention.

10, 10A to 10F Color filter 11 Transparent base 12, 12E, 12F White matrix layer (WM layer)
13 Frame portion 14 Overcoat layer 15, 15E White layer 16 Backing layer 17, 18 Black matrix layer (BM layer)
20, 30, 40 colored layer (first colored layer)
20D, 30D, 40D colored layer (second colored layer)
50, 50F Transmission prevention layer 51, 51F BM layer 52 Reflective layer 80 Reflection type display element 100, 100C, 100F Electronic paper

Claims (8)

A transparent substrate,
A white matrix layer for pixel division provided on the transparent substrate and forming a plurality of openings;
A transmission preventing layer provided on the inner surface of the plurality of openings of the white matrix layer;
A plurality of colored layers provided in the plurality of openings of the white matrix layer;
Color filter with A transparent substrate,
A plurality of colored layers provided on the transparent substrate and arranged with a predetermined gap therebetween;
A white matrix layer for pixel division which is provided in the gap between the colored layers, an end portion of which runs on the end portion of the colored layer to form an opening for exposing the plurality of colored layers;
A light transmission preventing layer provided on an inner surface of the opening at an end of the white matrix layer which is mounted on the colored layer;
Color filter with   The color filter according to claim 1, wherein the anti-transmission layer comprises a black matrix layer.   The color filter according to claim 1, wherein the transmission preventing layer has a reflective layer that reflects light.   The color filter according to claim 4, wherein the reflective layer comprises a metal layer.   The color filter according to any one of claims 1 to 5, wherein a thickness of the white matrix layer is thicker than a thickness of the colored layer. A color filter according to any one of claims 1 to 6;
A display element disposed to face the color filter;
A display device comprising:   The display device according to claim 7, wherein the display device is a reflective display device performing white display and black display.

Images